1. Field of the Invention
The present invention relates generally to magnetic heads for hard disk drives, and particularly to perpendicular magnetic heads having electroplated pole tips.
2. Description of the Prior Art
Hard disk drives generally include one or more rotatable data storage disks having a magnetic data storage layer formed thereon. Data in the form of small magnetized areas, termed magnetic data bits, is written onto the magnetic layers of the disks by a magnetic head that includes magnetic poles through which magnetic flux is caused to flow. Magnetic flux flowing from a pole tip portion of the magnetic poles in close proximity to the magnetic layer on the disk, causes the formation of the magnetic bits within the magnetic layer.
Generally, magnetic bits can be created where the magnetic field direction of each bit is either in the plane of the magnetic layer or perpendicular to the plane of the magnetic layer. Magnetic heads that form magnetic bits having in plane magnetic fields are termed longitudinal magnetic heads, whereas magnetic heads that form bits having a magnetic field that is perpendicular to the plane of the magnetic layer are termed perpendicular heads. The present invention relates particularly to perpendicular magnetic heads.
In order to increase the areal data storage density of the disks, it is desirable to write smaller magnetic bits. To accomplish this, it is necessary to fabricate magnetic heads having a smaller magnetic pole tip, because the dimensions of the pole tip directly determine the size of the magnetic data bit that is written by the pole tip. In currently fabricated magnetic heads, the pole tips are fabricated with submicron dimensions to produce submicron sized magnetic bits. Such submicron sized magnetic pole tips are quite fragile, and are easily malformed, and/or damaged during the magnetic head fabrication process. Particularly, some fabrication processes utilize a sputter deposition technique for fabricating the pole tips; however, this technique can lead to the creation of unwanted voids within the pole tip material. Where the pole tips are electroplated, the occurrence of voids is substantially reduced. Additionally, where the pole tip is fabricated earlier in the magnetic head fabrication process, rather than later, an increased occurrence of damage to the pole tips during subsequent fabrication steps occurs. The present invention seeks to resolve these problems by electroplating the pole tip in fabrication steps towards the end of the magnetic head fabrication process.